Mill-tube.



J. E. MILLER.

MILL TUBE.

APPLICATION FILED JULY 11. I9I6.

Patented Feb. 25, 1919.

2 SHEETS-SHEET] I f wwwtoz J. E. MILLER.

' MILL TUBE.

APPL/ICATION r1120 JULY 17. 1916.

Patented Feb. 25, 1919.

2 SHEETSSHEET 2.

gwuemlioz Qbtomw UNITED STATE PATENT QFFIQE..

JESSE MILLER, 01? KNOXVILLE, TENNESSEE.

MILL-TUBE.

Application filed July 17, 1916.

To all whom it may concern Be it known that I, JEssE E. MILLER, a citizen of the United States, residing at Knoxville, in the county of Knox and State of Tennessee, have invented a new and useful Improvement in Mill-Tubes, of which the following is a specification, reference be ing had to the accompanying drawing.

My invention relates particularly to such tubes as are used in flour mills for conducting the materials, in various stages of the operation, downward by gravity, and the object of the improvement is to form such tubes of sheet metal with suitable ports for the inspection of the material passing down ward through the tube and for the admission of means for dislodging the material when the latter becomes clogged.

Heretofore, such conducting tubes have in nearly all cases been made of wood and of rectangular cross-section. It is essential that such tubes be dust tight at all points, in order that no portion of the material passing through the tubes may escape into the mill. 'Such escape would be objectionable on account of loss of material and also on account of fogging the air in the mill. Making such wooden tubes dust'tight is difficult. It requires high mechanical skill, and only two or three varieties of wood are regarded as suitable for this purpose in this country, and these varieties are expensive. Hence these wooden tubes are objectionable on account of expensive material and expensive labor. They are further objectionable because they are combustible. v

In view of the foregoing, efi'orts have'been' made to substitute metal tubes for such wooden tubes; but this'has been found to be a difficult task. It would not be dilficult to make such tubing, if the inspection ports were not needed. But to apply such inspection ports in suitable form to the metal tubing is diflicult. They must be dust tight and they must be of such shape as not to interfere with the flow of material and they must be of suitable size to admit long strips of wood or other devices used for dislodging the material in distant portions of the tube when there is clogging. The port must be free from angles or sharp edges which will interfere with the insertion of such a dislodgingdevice or the insertion of the hand either up or down the tube. Furthermore, the devices surrounding the ort and forming its closing means must e durable and Specification of Letters Patent.

Patented Feb. 25, 1919.

Serial No. 109,841.

inexpensive. In the ordinary flouring mill large numbers of such tubes are used and the total number of such ports is large, and if the construction is expensive the aggregat cost burden becomes excessive.

Furthermore, the operation of opening and closing the port must be easy and simple.

Letters Patent of the United States, No. 1,162,502, granted to me November 30, 1915, describe 'a construction comprising a sheet metal tube and a port meeting the abovementioned requirements. The present invention comprises a similar structure with another form of the port mechanism.

In the accompanying drawings,

Figure 1 is a front elevation of a piece of sheet metal tubing embodying my improvement;

Fig. 2 is a right-hand side elevation of the mechanism shown by Fig. 1, portions being broken away;

Fig. 3 is a section on the line, 3-3, of Figs. 1 and 2;

Fig. 4 is a section on the line, 4+4, of Figs. 1 and 2;

Fig. 5 is a section on the line, 5- -5, of Figs. 1 and 3;

, Fig. 6 is a plan of a fiat sheet metal blank used for forming the port body;

door.

Referring to Figs. 1, 2, 3, 4, and 5, A is a cylindrical, sheet metal, mill tube which is to be provided with a port. This is accomplished by attaching to the front of the tube a port body, B, which has at its front an opening to which a door, G, is applied, the wall of the tube being cut away within the port body.

For convenience in description, an imaginary line extending lengthwise on the face of the tube through the line, 55, of Fig. 3, is called the front quarter line, while a similar imaginary line extending length wise on the rear of the tube through said line, 5-5, is called the rear quarter line, and similar lines extending lengthwise on each side of the tube midway between the front quarter line and the rear. quarter lineare called the side quarter lines; and the portion of the tube between the front quarter line and the right-hand side quarter line .is called the right-hand front quarter of the tube, and the portion ofthe tube between the front quarter line and the leftthe right-hand quarter line is called the right-hand rear quarter of the tube, and the portion of the tube between the rear quarter line and the left-hand side quarter line is called the left-hand rear quarter of the tube.

The sheet metal blank illustrated by Fig. 6 is cut with reference to the tube, A, in order that the finished port body may fit to the curvature of approximately the front half of the cylindrical tube (the portion forward of the side quarter lines) and may extend for enough forward away from the tube to permit the placing of the door in position on said body without extending into the cylindrical space represented by said tube. Before said blank is cut, it is in the form of a parallelogram having a length approximately equal to twice the height and twice the width of the port body. On said blank are three centers, B placed equidistant from each other on a line, B which is at a short distance from and parallel to the rear side edge (the left-hand edge in Fig. 6) of the blank, one of said centers being at the middle of the length of the blank, and each of the others being close to the end of the blank.

On the middle center, B are drawn two concentric semicircle lines, B and B both extending from the line, B toward the right on Fig. 6 and again to said line, the line,

B being drawn outside of the line, B and on a radius equaling the radius of the tube to which the finished port body is to be applied. And on each center, B, are drawn two quarter circle lines, B and B*, said lines extending from the line, B around said center to the line, B, which cuts the end centers,- B perpendicularly to said line, B and the qua1ter-circle line, B, being outside of the quarter-circle line, B and drawn on aradius which equals the radius of said tube. At each end of the blank, the line, B*, and the adjacent center, B represent a quarter circle, while at the middle of the blank, the line, B and the adjacent center, B represent two quarter circles. Thus the blank represents four quarter circles each of which conforms in dimensions to a cross sectlonal quarter of saidtube. Straight lines, 13 and B are extended from the lines, B and B, respectively, to the adjacent end edge of the blank. A bending line, B,

' is drawn tangentially to'each quarter circle,

and perpendicularly to the line, B and extending from said line across the blank to the right-hand or outer edge of the blank.

About a quarter of an inch from the outer side edge of the blank (the side the farther from the line, B is placed a bending line, B. At the junctions of the line, B with the quarter circles, B, and the half circle, B a line,B is drawn. to the adjacent edge of the blank and parallel to the adjacent livne,B and perpendicularly to the line, B

Next the sheet metal is out along the quarter circle lines, B", the lines, 13 and the lines, B and along the half circle line, B, and the" adjacent lines, B A slit, B is out along the line, B from each line, B, to the adjacent line, B. Along the quarter circle lines, 13*, and B, slits, B, are cut in the metal from one of said lines to the other and radially to the adjacent center, B

The portion of the blank between the line, B, and the adjacent side edge of the blank is a bead strip. This strip is now folded over on the line, B, to lie against the ad jacent portion of the blank and form a bead, B. The portion, B between the line, B and the parallel edge of the blank, at.each end of the latter, forms an over-lapping portion, as will be shown farther on.

The blank is now bent to right-angles on the two middle bending lines, B, said lines extending only from the line, B to the beaded side edge, and the bending on each line being in the same direction, preferably in the direction which will bring the bead onthe outside. This bending brings the portions, 13", of the blank between each mid? dle line, B and the nearer line, 13*", parallel to each other. The blank is alsofbent in the same direction on each end line, B. This causes the portion, B of the blank above the upper line, B and the portion, B below the lower line, B to meet,,the narrow portions, B over-lapping. Theseoverlapping portions are joined to each other in any suitable manner, as by soldering.

The metal between the slits, B is now bent outward to stand perpendicularly to the adjacent end wall, B of the rectangular body thus formed. Thus we have in said end wall a semicircular opening of the dimensions of one-half the cross section of the tube, A.

At the other end of the structure, the metal between the semi-circle lines, B and B is spun or swaged outward until it is perpendicular to the adjacent end wall, B of the structure, the portion lying between the line, B and the bead, B Thismetal may be slitted and then bent outward, as described regarding the metal lying between the lines, B and B and the slitting of the metal between said lines, B and B may be omitted and the metal spun or swaged 'outi'vard. Both of these methods are illustrated and described, because either. is suited to the purpose.

It is to be remembered that the bending on the lines, B extends only from the bead edge to the line, B Hence the metal be-. tween the slits, B and the adjacent side quarter lines of the tube.

edge of the blank was not bent but was left in the plane of the flat portions, B"the portionsof the blank forming the upright sides of the rectangular body.

The structure now has at each end and forward of the lines, B a semi-circular opening of the size of one-half of the crosssection of the tube, A, and adapted to receive said half, the portions or extensions, B rearward of the line, B extending rearward of the side quarter lines of the tube. Said extensions, B are both curved to make them concentric with the axis of said cylinder, in order that they will fit closely against the outer face of the cylinder. When this has been done, the distance between said extensions is normally less than the diameter of the tube, and therefore the port body is to be applied to a tube section by moving the two members endwise over each other or by pressing the port body laterally against the tube section and thus causing the portions, B to spring apart until they have passed the thicker portion of the tube. When the body has been thus formed and placed on the tube, the metal bent outward along the semi-circular lines forms a flange at the upper end and at the lower end of the body, B extending from one extension, B to the other and fitting against the outer face of the tube.

The port body is now pushed endwise and turned crosswise into the position which it is to occupy in the finished structure. That position is next indicated by marks placed on the tube along the outer edges of the port bodythe outer edges. of the flanges, 13 and the extensions, B Then within the port body, the outer face of the tube is marked horizontally approximately flush with the inner faces of the upper and lower end walls, B of the port body, said walls being used as guides forthe marking instrument. The port body is then removed. Then the cross lines on the tube are connected by upright lines drawn parallel to the upright marking lines drawn on the tube along the outer edges of the extension, B and at a distance from said marking lines equal to the width of the extensions, B Thus the last marking lines placed 'on the tube will coincide with the imaginary side The tube is next cutalong the upper and the lower cross lines and along the two upright lines which connect the cross lines. The rectangular piece of metal thus released is removed, leaving a rectangular opening.

The tube is now ready to receive the port body permanently. Said body is again put into position on the tube, according to the markings previously made, and then the edges of the portions, B and the flanges, 3 are secured to the face of the tube, as by means of solder.

V The port body is now ready to receive the door, C. This may be any rectangular body adapted to fit dust-tight between the four walls of the port body. The drawings illustrate a preferred form of such door.

Fig. 7 illustrates a sheet metal blank from which the door is made. This blank is of rectangular form. Bending and cutting lines, C, extend parallel to the four edges of the blank; and inward of each of said lines is a cutting and bending line, C, also parallel to said edge. The metal is cut from the edge to the four intersections of the lines, C, outward on said lines. Then the metal is bent outward along the lines, C, until it is nearl perpendicular to the rectangular body, 0, which is bounded by the lines, C and C The portions of the metal outside of the lines, C, are turned rearward to form a. hook, C along each of the four edges of the-door. The dimensions of the rectangular body, C are made a little less than the dimensions of the rectangular opening in the port body, so that the outer or front portions of the walls. 0' and C of the door will constitute wings slightly inclined toward and bearing against the correspondin walls of the port body, while the hooks, extend over the edges of said walls of the port body. The end edges of the side walls, C and C of the door will substantially meet, and they may be soldered to each other. But, as above indicated, said walls are preferably slightly inclined relative to the body, C in order that the door will be adapted to wedge into the opening of the port body. In this connection, the flexibility of the walls, C and C, may be utilized, and this action may be augmented by leaving the meeting end edges of said walls free from each other. A member, D, is applied to the rectangular'body, C of the door in such manner as to serve as a handle and also as a means for imparting rigidity to the body of the door. Said member is a piece of channel metal with its back laid against the front of the body, C of the door and having its flanges, D out near each end and laid horizontally to form ears, D Rivets, D extend through said ears and the back of said member and through the body, C of the door, whereby said body and said member are firmly secured to each other. Said member imparts stability to th body, C of; the door; and said member may be grasped by the hand for moving said door into and out of position.

In practice, the port body and the door are to be manufactured in any desired numbers and to fit mill tubes of chosen diameters. Then, during installation in the mill, the port bodies are applied to the tubes where needed and in the manner above described, the body being first placed in position forthe marking of the tube and their" removed for the cutting of the tube, and so on. The port body is made as long, meas ured up, and down, as may be deemed suitable for the convenient insertion of the hand and arm of an operator or any tool used for removing lodged material in the tube.

This construction permits the use of indefinite quantities of the cylindrical sheet metal mill tubing made entirely Without reference to the location of ports; and the port body and door may be cheaply and accurately manufactured in chosen sizes and applied where needed. The finished structure is dust-tight, strong, durable and incombustible. I

It is to be understood that my improvement is applicable to all kinds of mills and grain elevators and similar plants for handling cereals and seeds.

It is also to be noted that suitable dies may be made andused for forming the port body and the door.

I claim as my invention,

1. In the art herein described, the combination with a tube positioned for gravity flow of the material herein described and having a lateral rectangular port extending across one-half of the circumference of said tube, of a sheet-metal port body having a door opening conforming to said port and said port body having flanges located at the sides of said port and conforming to the exterior face of the tube and extending beyond the quarter lines of the tube and converging and engaging the tube, substantially as described.

2. In the art herein described, the combination with a tube positioned for gravity flow of the material herein described and having a lateral, rectangular port extending across one-half of the circumference of said tube, of a sheet-metal port body having a door opening conforming to said tube opening and said port body having end flanges and side flanges conforming to the exterior faceof the tube and said side flanges extending beyond the quarter lines of the tube and converging and engaging the tube, substantially as described.

3. In the art herein described, the combination of a door and a sheet metal port body having an opening conforming to the interior ofthe port body and adapted to receive the door and having end portions and side portions shaped to conform to the exterior face of a cylindrical tub and to be secured dust-tight to the face of said tube, the said side portions extending rearward of the side quarter lines of said tube and engaging the tube, substantially as described. 7

4:. In the art herein described, the combination of a door and a sheet-metal port body having an opening conforming to the interior of the port body and adapted to receive the door and having end portions and terior face of'a cylindrical tube andto be.

secured to the faceof said tube, the said side portions extending beyond the'quarter lines k of the tube and having marks indicating the positions of the quarter lines, whereby said port body is adapted to use in marking said tube for cutting the port opening in the tube, substantially as described.

5,. In the art herein described, the combi nation of a door and a sheet metal port body having an opening conforming to the interiorf' of the port body and adapted to receive the door and having end portions and side portions shaped to conform to the exterior face of a cylindrical tube and to be secured dust-tight to the face, of said tube, the said side portions extending rearward of and having their edges parallel to the side quarter lines of said tube and engaging the tube, substantially as, described.

6; In the art herein described-the combination of a door having flexible edge walls standing approximately perpendicular to it body, and 'a sheet metal port body having Walls parallel to, th edge walls of "the door and forming an opening adapted to receive the do I' and having end portions and side portions. shaped to conform to the exterior face of a cylindrical tube and to be secured dust-tight to the face of said tube, subs-tantially as described.

7.. In the art herein described, th combination of a door having flexible edge walls standing approximately perpendicular to its body, and a sheet metal port body having walls parallel to the edge walls of the door and forming an opening adapted to receive the door and having end portions and side portions shaped to conform to the exterior face of a cylindrical tube and to be secured dust-tight to the face of said tube,'the said side portions extending rearward of the side.

quarter lines of said tube, substantially as described.

8. In the art herein described, the combination of a door having flexible edge walls standing approximately perpendicular to its body, and a sheet metal port body having walls parallel to the edge walls of the door and forming an opening adapted to receive the door and having end portions and side portions shaped to conform to the exterior face of a cylindrical tube and to be secured dust-tight to the face of said tube, the said side portions being adapted to serve as aids for the location of the side quarter lines on said tube preparatory to cutting the wall of the tube, substantially as described.

9. In the art herein described, the combination of a door-having flexible edge walls standing approximately perpendicular to its body, and a sheet metal port body having walls parallel to the edge walls of the door and forming an opening adapted to receive the door and having end portions and side portions shaped to conform to the exterior face of a cylindrical tube and to be secured dust-tight to the face of said tube, the said side portions extending rearward of and having their edges parallel to the side quarter lines of said tube, substantially as described.

10. In the art herein described, an elongated sheet metal blank beaded on one edge and having quarter circle openings formed in the other edge of dimensions corresponding to the quarters of a sheet metal mill tube, and the distance between said quarters being equal to the desired height of the sides of a port body to be applied to said sheet metal tube, substantially as described.

11. In the art herein described, an elongated sheet metal blank beaded on one edge and having quarter circle openings formed in the other edge of dimensions corresponding to the quarters of a sheet metal mill tube, and the distance between said quarters being equal to the desired height of the sides of a port body to be applied to said sheet metal tube, said quarter circle openings having portions to be bent perpendicular to the blank to form flanges, substantially as described.

12. In the art herein described, an elongated sheet metal blank beaded on one edge and having quarter circle openings located inward of the edge of the blank which is opposite the beaded edge, said openings being of dimensions corresponding to the quarters of a sheet metal tube, and the distance between said quarters being equal to the desired height of the sides of a port body to be applied to said sheet metal tube, substantially as described.

13. In the art herein described, the method of forming a port hole for a port body, which method consists in forming the port body with side walls and end walls, the end walls having semi-circular openings to receive the front half of a sheet metal tube, then placing said body on said tube and using the inner faces of the end walls of said body as guides for marking cross lines on the tube and using the rear edges of the sides of said body for marking upright lines connecting said cross lines approximately coincident with the side quarter lines of the tube, substantially as described.

In testimony whereof I have signed my name this 7th day of July, in the year one thousand nine hundred and sixteen.

JESSE E. MILLER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

